Back and neck pain is a significant problem for many people, and several types of therapeutic pillows have been developed to help relieve this pain. One type of pillow provides improved cervical support by having an indentation to receive the head and a bulbous portion to support the neck. One general principle behind these pillows is to provide a comfortable sleeping surface for the head, while providing cervical support for the neck, thereby reducing muscle tension in the neck. For example the Mediflow.RTM. pillow, U.S. Pat. Nos. 4,947,931 and 4,896,388, has a soft-fibre upper layer and a water-filled bag lower layer. In use, the pillow adapts to the contours of the head and neck thereby providing appropriate head and neck support.
The foregoing prior art is useful for relieving back and neck pain, however, it has been found that a contributing factor to back and/or neck pain is poor sleeping habits. One poor sleeping habit is the tendency for some people to sleep face-down, rather than on their side and/or on their back. For greater clarity, as used herein the term "face-down" refers to a person sleeping with his or her front-side down, wherein the person's chest and stomach are lying on the sleeping surface and typically the person's head is twisted to one side. As is known to those of skill in the art, sleeping face-down can place stress on certain muscles and cause particular strain in the back and/or neck. After sleeping face-down, persons can awake and find themselves sore and stiff. Persons who have chronic pain can find themselves in even greater discomfort after sleeping face-down. One problem with the prior art is that persons who habitually sleep face-down can simply sleep face-down on the pillow or unconsciously discard or flip the pillow over to use the flat side of the pillow, such that it is relatively comfortable for sleeping face-down.
In contrast to the foregoing, the Materna-mate.RTM. pillow, as found in U.S. Design Pat. No. 298,715, supports a pregnant woman lying on her side or on her back, but makes it difficult for her to sleep on her front. The Materna-mate.RTM. is characterized by a flat bottom and a concave upper portion, defined by a thin central portion and a pair of wedge-shaped side portions which slope downwardly towards the central portion. The pillow can be used about the waist area of the pregnant woman to provide support about the middle and lower back. The pillow can assist keeping a pregnant woman more comfortable during sleeping and sitting. It will be apparent, however, that the Materna-mate.RTM. does not provide head and neck support and is best suited to the unique needs of a pregnant woman, and is generally unsuitable for training a person not to sleep face-down.
It will be apparent from the foregoing that prior art pillows are generally designed to relieve back and neck stress and provide support, but are generally unsuitable for training a person to sleep on his or her back and/or side.